1. Field of the Invention
The present invention relates to a structure of a cylinder block.
2. Description of the Related Art
Generally, a skirt portion, the lower structure of a cylinder block for an engine (an internal combustion engine), forms a crankcase to contain a crankshaft.
For example, an accompanying drawing FIG. 8 schematically illustrates a cylinder block for an engine (a V-engine) seen from the axis direction of a crankshaft. As shown in FIG. 8, a crankshaft 3 is arranged inside a skirt portion 2 of the cylinder block 1. The crankshaft 3 is mounted, via bearings (bearing metals, not shown), on bearing mechanisms 4 formed in the cylinder block 1 and bearing caps 5 are attached to bottom of the bearing mechanisms 4 in order to fix the bearings of the crankshaft 3. The bearing mechanisms 4 are placed at both ends and appropriate intermediate portions of the engine. A bearing cap 5 is mounted on each of the bearing mechanisms 4.
In order to fasten the bearing caps 5 to the cylinder block 1, beams 6 in the separated form from the bearing caps 5 are to attached to each bearing cap 5. Each beam 6 is disposed at the skirt portion 2 of the cylinder block 1 in such a direction that the beam 6 extends in the crosswise direction (perpendicular to the crankshaft 3) of the engine. The both end of each beam 6 is fixed to the skirt portion by bolts 7 and the intermediate portion between the both ends is fixed, together with the corresponding bearing cap 5, to the bearing mechanism 4 by longer bolts 8.
An oil pan (however not shown) is arranged under the skirt portion 2 (under the beams 6) of the cylinder block 1 and store a drain of an engine oil serving as a lubricant in the cylinder block 1. Further, a baffle plate is placed between the top of the oil pan and the bottom of the beams 6.
In relation to such a technique for a skirt portion of a cylinder block, for example, Japanese Utility Model Publication No. HEI 6-27770 discloses a baffle plate, attached to the bottom of a cylinder block, forms along the rotation path of a crank axis and includes a reinforcement rib.